A multicomponent process for the preparation of piperidinium 2-oxo-3,5-dicyano-4-cyclohexane(pentane)-spiro-1,2,3,4-tetrahydropyridine-6-thiolates (I) and derivatives thereof (II)

摘要

A multicomponent process for the preparation of piperidinium 2-oxo-3,5-dicyano-4-cyclohexane(pentane)-spiro-1,2,3,4-tetrahydropyridine-6-thiolates (I) and derivatives thereof (II). According to the process cyclohexane(penta)nones (III) are subjected to successive interaction with cyanoacetic ester (IV) and cyanithioacetamide (V) in the presence of piperidine in ethanol medium at 20 °C. After dissolution of initial reactants the mixture is filtered, fine-crystalline precipitate is separated, washed with acetone, and products (I) are obtained. Due to short-term heating of the products with alkyl halides (VI) in ethanol and washing of fine-crystalline precipitate with ethanol and hexane the derivatives (H) are prepared with 61-83% yield.